I know, it’s an extremely stupid issue!
Here is the solution:
Just go to /usr/share/themes/Adwaita/gtk-3.0/ and add the following text to the file named gtk.css:
text-shadow: 1px 1px @desktop_item_text_shadow;
background-color: alpha(#D64A38, 0.9);
You can replace Adwaita with whatever theme you’re using and the color codes to whichever colors you choose (#FFFFFF is for white, which is perfect for me)
Credit goes to herunotenchi on https://github.com/linuxmint/Cinnamon/issues/3226